/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.flume.node.nodemanager;

import java.util.HashSet;
import java.util.Set;

import org.apache.flume.lifecycle.LifecycleAware;
import org.apache.flume.node.NodeManager;

import com.google.common.base.Preconditions;

abstract public class AbstractLogicalNodeManager implements NodeManager {

  private Set<LifecycleAware> nodes;

  public AbstractLogicalNodeManager() {
    nodes = new HashSet<LifecycleAware>();
  }

  @Override
  public boolean add(LifecycleAware node) {
    Preconditions.checkNotNull(node);

    return nodes.add(node);
  }

  @Override
  public boolean remove(LifecycleAware node) {
    Preconditions.checkNotNull(node);

    return nodes.remove(node);
  }

  @Override
  public Set<LifecycleAware> getNodes() {
    return nodes;
  }

  @Override
  public void setNodes(Set<LifecycleAware> nodes) {
    Preconditions.checkNotNull(nodes);

    this.nodes = new HashSet<LifecycleAware>(nodes);
  }

  @Override
  public String toString() {
    return "{ nodes:" + nodes + " }";
  }

}
